Printing ink



Patented Mar. 2, 1948 PRINTING INK Richard A. Benton, River-ton, Chemical Corporation,

No Drawing. Application January 29, 1944,

Serial No. 520,320

3 Claims. (01. zoo-7) This invention relates to printing inks, and more particularly to inks which are to be set, or dried, by applying water (for example, as water, steam, spray) immediately after printing,

such inks being generally referred to as steam or water-setting inks.

Such an ink, in its necessary characteristics, presents the conflicting requirements that while it mus have suflicient "pres stability so that in use it will distribute readily upon the printing 10 rolls, without setting up or hardening or pulling away from the roll under all operating conditions of pressroom humidity, nevertheless it must be suiiic iently responsive that is, harden to non-offsetting conditionswith great rapidity. In fact, to meet the requirements of modern high speed printing presses, such an ink must set almostin'stantly' upon the moisture application.

It is an object of the presentinvention to provide an ink compositiomsuitabie'ior use in the moisture setting process whlchhas high press sta.. bility under all pressroom operating conditions of humidity and which can be set with great as to the moisture which is applied after printing so that it will dry or set N. 1., assignor to a corporation of i referred to contain a water precipitablw r component dissolved or dispersed in a vp cible solvent component so that upo: application or the like, after printing th 1 t l be diluted or removed to sue an t t t at th binder will be precipitat d or sef Many such water precipitable giders, which are soluble in water-m sci le s vents, although usable to pre- Dar S t l lr'ks' for ordinary printing processes, have been found to be completely unsatisfactory for the preparation of steam-setting or watert the printed surface of waty'tier spray, steam ig fin g inks, The reason for thlsunsatisfactory ondition seems to be that such water insolublebinder-water-miscible solvent systems are sufiiciently sensitive to absorption of moisture fi m the air so that even slight change in relative humidity of the atmosphere in which they are used or stored may causethe setting action, For

, example, when the'amount of water vapor in the,

atmosphere is relatively high, say above to-5Q *perceht r'elative humidity, there is atendency for such water precipitable binder-water-miscible solvent systems to absorb moisture from the-atmosphere to such' an rapidity aft r printing by application of moisitatio'n or settingof the water-insoluble binj .wh imprinted, sets with extreme rapidity on application moisture thereto. v

Another object o he insvention is to provide Thus when inks which containsuch yst are usedfor printing when the relative humidity of the atmosphere arcuiimthe press is high there is theob iectionable tendency to set and harden oii'the press, with the result that unsatisfactory orpoor printing results. The term water sensitive as used in this application with reference to moisture-setting inks means that the ink is a printing ink of the characterdeseribed'adapted sample or lwt to deterioration or failure'on' for use in the moisture setting processgwhich flvpfssrolls throughthe action or absorption water spray, steam, a water bath. or the like),

but nevertheless the ink and its constituent components such as the binder in solution, have such press stability as to resist objectionable setting or precipitation by action or absorption of atinicspheric moisture even at high relative humidt es.

of moisture in the atmosphere, and as a result, the ink fails to remain open on the press and either hardens or sets on the press and before 40 printing, or fails to follow the printing rolls and to distribute properly thereon, or exhibits some other similar operating failure attributable to absorption by the vehicle, system of sufficient moisture from the atmosphere, in greater or less degree depending on the nature of thevehicle to which is applicable for use in moisture setting processes for printing, and which is press stable in operation even under extremely high humidity conditions of pressroom operation, up to per cent relative humidity or higher, and which will Steam or water setting inks of the kind herein .86 set substantially instantly to non-offsetting conextent as to cause precip ditions. when imprinted, upon application of Examples f sati factorily used inks, with difmoi t theretq Iering types of binders, are illustrated by the ex- Among water insoluble binders usable in such amples which are described hereinaft r,

water or steam setting compositions having extremely rapid water setting characteristics. ex- 8 Example I cellent gloss and good pigment binding charac- Parts by weight teristics on printing are the alcohol soluble pro- Zein 8 0 teins such as the proiamines. including the corn Tri thanolamine resinate 6.5 protein zein. as well as shellac. rosin. ester gum. Phenol resin 12.0 the maleic acid-terpene resins. the maleic modi- 10 Water 4,0 tied rosin glyceride resins. the maleic modified pr py e e glycol 18.0 rosin resins. the phenol modified cumar resins, methylene glycol 30.0 nitrocellulose. cellulose esters and ethers and Ca bon black 16.0 mixtures thereof. In general. film torming-ma- Alkali blue pigment 1.0 terials insoluble in water and soluble or disper- Milori blue pigment 2.5 sible in water-miscible solvents are adequately Violet toner 2.0 f satisfactory for use in such inks, the particular V hinder or mixture of binders used depending up- 100.0% gait: end characteristic of printing mammals The phenol resin of Example No. l is an alcohol soluble phenol aldehyde condensation product.

This ink was printed on a commercial press on a day when the relative humidity in the'pressroom was 75%. The printing operation lasted for 40 minutes during which time no caking or setting up on the rolls occurred, and when the printing operation was discontinued the ink was still open" on the rolls and was operating satisfac- Such binders may now be used. according to the invention. to prepare satisfactory steam or watersetting inks which combine ease of steam or water setting with freedom from drying or setting on the presses at high relative humidity, and also with good distribution on the rolls of the printing presses. And these inksalso are stable on the press under conditions of low relative humidity,

as for exam le. when the relative humidity is betorfly' low about 40%, o Example II In the inks of my invention. there is utilized Parts by Weight as part of the ink composition in connection with z m 13 a water precipitable binder component. a resinate Triethanolamme resmate 5 of an aliphatic alkylolamine. When such a res- \methylene glycol 5 inate is employed as part or the composition in w t f 25 such steam setting or water setting inks. ink comcarbon black 15,0 positions are obtained which will remain open and m blue pigment 4,5 distribute on the'press rolls under pressroom opa crating conditions and which are stable against 100.0% all pressroom humidity conditions. ranging up- 40 s wards to as high as 85 per cent relativehum'idity, This mkvgerated satisfactorily and remained iahpressior over an hour a and yet which when imprinted will set to non- Open on commerc ofl'setting condition as rapidly as the less press day when the relative humidity m the pressmom b was 60%, and was still operating satisfactorily 252622 1 233 223 g g g with no evidence of setting up when the printing operation was discontinued after an hour. 2 22 g g of lz fi gg igiig g gg Angther ink which was similar in composition relative humiities .to the above, except that no triethanolamine resinate'was used, and a. phenol resin used in place For illustrative urposes, sew examples are hereinafter given of inks which contain ink've thereof failed to print at an under the same hicles comprising water precipitable binder-waga fqeg fit fi gg gfigz gg gg ter-miscible solvent systems of the invention. It 0 w f i will be understood that in the examples given, the'addmon to e on 0 var ous ts such asgen'EraHy are used in the r the particular proportions oi! water insoluble Wetting-i161! or 7 binder materialTwater-miscible"solventvandmigr to improve this property ment represent formulations which have been trample III -round.g imverygsatisfactory results in printing 7 T ti0ns. butthe relative proportions may be Parts by g i varied to meet the particular conditions required zem 4- for the kind of press used, its operating or print. 50 Tr t an lamine resinate 2 .9 ing speeds, and paper as customarily is done in P1161101 3- t printing industry. as well understood by those h ne g ycol .3 skilled in the art. Further, all the formulation lo i blue pi ment 2. iven below are for a black ink, but the particu- Carbon b lar coloring material, pigments and dyestufis. if 100 07 desired, may, of course, be varied to give the color 0 requirements o y pa t cular printing Jo or The phenol resin of'Example III is also an alcop i n just as in other inks. The inks deho! soluble phenol aldehyde condensation product. scribed are prepared by the conventional mixing This ink was tested in comparison with a comand grin ing operation Well kn wn t the ink i mercial ink containing a prolamine but containdustry. The vehicles are prepared by dissolving ing no resinate of an aliphatic alkylolamine. or dispersing the binder components in the 501- The printing operation was made by spreading vent component in the cold, or by gentle warming, or "tapping out" the ink on glass plates at a relas is customary in preparing such types of ink ative humidity of approximately 100%. The vehicles. inkof Example III remained "open" and workable during the entire length of the test, which was about 2 hours, and the ink was still in satisfactory open" condition when the test was discontinued after the elapsed time mentioned. The commercial ink containing no triethanolamine resinate on the other hand, failed almost instantly under the described conditions, by setting up and hardening on the plate.

Example IV Parts by weight Shellac (dewaxed) 19.0 Triethanolamine resinate 19.0 Diethylene glycol 39.0 Carbon black 18.0 Milori blue pigment 5.0

Maleic-rosin modified resin 28.8 Triethanolamine resinate 14.4 Diethylene glycol 33.8 Carbon black 18.0 Milori blu pigment 5.0

- A 100.0% The maleic type resin referred to above is one of those comprising a rosin modified with an alpha beta unsaturated organic polybasic acid, such as maleic acid or fumaric acid, as described in Patent No. 2,063,542 issued December 8, 1936, to Carleton Ellis. Such type of resin has a high acid number of about 300'and a melting or softening point above the temperature of ordinary steam, e. g. about 130 C.

This ink was printed on a Hacker proof press at pressroom relative humidity at 78% and at 74 F. and printed satisfactorily for 40 minutes, and was printing well when the operation was discontinued after that time. An identical ink, except that it contained only the maleic rosin resin as a binder-i. c. it had no triethanolamine resinateprinted satisfactorily, for only 2 minutes, at which time hardening began tooccur, and the ink was completely dry and hard on the press after 17 minutes.

I Example VI- Parts by weight Terpene maleic resin 16.6 Triethanolamine resinate 33.2 Oiethylene glycol 27.2 Carbon black 18.0 Milori blue pigment 5.0

The terpene maleic resin is likewise a maleic type resin, as described generally above.

This ink was printed on a Hacker proof press at pressroom relative humidity of 16% and distributed and printed well for 15 minutes after which hardening began to occur. An identical ink, except that the terpene maleie-resin, with no alkylolamine resinate present, was used as the sole binder constituent failed completely to 76.-

being borne in mind that no fresh ink 6 distribute on the printing rolls and no prints whatever could be obtained. a striking example of the eflect of the triethanolamine resinateit was added during this short operation.

As set out in the above illustrative examples the percentage of alkylolamine resinate satisfactory to secure the result above set forth is within the ranges of 4% to 33% by weight of the ink and Within the ran e of 5% to 43% by weight of the ink vehicle.

In the above the alkylolamine resinate referred to is in each instance given as the triethanolamine resinate, as this is made from readily available materials and may be readily prepared. But this is for purposes of description and is not intended to exclude the monoand dialkylolamine resinates. Triethanolamine resinate can readily be prepared by mixing about 61% osin by weight with about 26% triethanolamine, heating to 250 F. with stirring until homogeneous, cooling to 200 F. and adding 13% water. The described method is given as illustrative of a way of producing a satisfactory heat-reacted alkylolamine resinate material which is slightly on the alkaline side, and thus will not react with basic pigments to produce livering, gelling or other deleterious results of this nature. Also the triethanolamine is less strongly alkaline than the monoand di-alkylolamines, and therefore requires less neutralizing acid material than either the monoor the di-forms. The preparation of triethanolamine resinate is illustrative of treatment of the alkylolamine to produce a constituent which may be included in the vehicle or in the complete ink to give the desired resistance of the water miscible solvent and water'precipitable binder to the action or absorption of moisture from the air and in which the percentage of rosin used is kept within practicable working proportions, inasmuch as in some inks rosin in too large proportion may adversely affect the binder characteristics of the set or dried ink. But if the proportions of components in the vehicle or in the finished ink are such that a larger proportion of resinate with the proportion of alkylolamine having its alkalinity suitably reduced, does not adversely affect the binding characteristics of the imprinted ink then in such event the triethanolamine ester would not necessarily be any more advantageous than the combined monoor di-alkylolamine having the requisite reduction in its alkalinity.

Any water-miscible organic materials which are solvents for the bindermaterials used such as the glycols' and their ethers can be used as solvents for the ink compositions described. Such solvents include diethylene glycol, triethylene glycol, dipropylene glycol, butyl ether of diethylene glycol and the like. Also other watermiscible solvents which are solvents for water insoluble binder materials may be employed for the particular printing operation, provided the solvent used is one which has adequate press stability at normal press temperatures and conditions of use, such that there is no objectionable evaporation of the solvent component during the printing operations-e. g. in the fountain or on the press rolls and distributing mechanism of a typographic pressso that the resulting ink is also adequately press stable against atmospheric moisture.

While the inks and ink composition, and the controlling constituents thereof, as described represent preferred embodiments of the invention it 7 is to be understood that the invention is not limited to such precise embodiments. and that changes may be made therein without departure from the proper scope of the invention as described and as defined in the appended claims.

What is claimed is:

1. A printing ink vehicle of the character described which is press stable at normal pressroom temperatures, comprising as essential ingredients in admixture a solvent for the binder which is also water-miscible and which is selected from the group consisting of water-soluble glycols and monoethers thereof, a water precipitatable binder constituent in said solvent, and heat-reacted neutral resinate of an alkylolamine in proportion falling within the range of per cent to 43 per cent of said vehicle.

2. A printing ink vehicle of the character described which is press stable at normal pressroom temperatures, comprising as essential in-' gredients in admixture a solvent for the binder which is also water-miscible and which is selected from the group consisting of water-soluble glycols and monoethers thereof, a water precipitatable binder constituent in said solvent. and a heat-reacted neutral triethanolamine resinate in proportion falling within the range of 5 per cent to 43 per cent of said vehicle.

. 3. A printing ink of the character described which is press stable at normal pressroom temperatures, comprising coloring matter dispersed in a vehicle comprising as essential ingredients in admixture a solvent for the binder which is also water-miscible and which is selected from the group consisting of water-soluble glycols and monoethers thereof, a water precipitatable prolamine binder constituent in said solvent, and a heat-reacted neutral resinate of an alkylolamine in proportion falling within the range of 4 per cent to 33 per cent of said ink.

4. A printing ink of the character described which is press stable at normal pressroom temperatures, comprising coloring matter dispersed in a vehicle comprising as essential ingredients" in admixture a solvent for the binder which is also water-miscible and which is selected from the group consisting of water-soluble glycols and monoethers thereof, a water precipitatable binder constituent comprising a prolamine and a 100 per cent phenol aldehyde resin soluble in said solvent, and a heat-reacted neutral resinate of an alkylolamine in proportion falling within the range of 4 per cent to 33 per cent of said ink.

5. A printing ink of the character described which is press stable at normal pressroom temperatures, comprising coloring matter dispersed in a vehicle comprising as essential ingredients in admixture a solvent for the binder which is also water-miscible and which is selected from the group consisting of water-soluble glycols and monoethers thereof, a water precipitatable rosinmaleic type binder constituent in said solvent, and a heat-reacted neutral resinate of an alkylolamine in proportion falling within the range of 4 per cent to 33 per cent of said ink.

6. A printing ink of the character described which is press stable at normal pressroom temperatures, comprising coloring matter dispersed in a vehicle comprising as essential ingredients in admixture a solvent for the binder which is also water-miscible and which is selected from the group consisting of water-soluble glycols and monoethers thereof, awater precipitatable prolamine binder constituent in said solvent, and a heat-reacted neutral triethanolamine resinate in proportion falling within the range of 4 per cent to 33 per cent of said ink.

' '7. A printing ink of the character described which is press stable at normal pressroom temperatures, comprising coloring matter dispersed in a vehicle comprising as essential ingredients in admixture a solvent for the binder which is also water-miscible and which-is selected from the group consisting of water-soluble glycols and monoethers thereof, a water precipitatable binder constituent comprising a prolamine and a per cent phenol aldehyde resin soluble in said solvent, and a heat-reacted neutral triethanolamine resinate in proportion falling within the range of 4 per cent to 33 per cent of said ink.

8. A printing ink of the character'described which is press stable at normal pressroom temperatures, comprising coloring matter dispersed in a vehicle comprising as essential ingredients in admixture a solvent for the binder which is also water-miscible and which is selected from the group consisting of water-soluble glycols and monoethers thereof, a water precipitatable rosinmaleic type binder constituent in said solvent, and a heat-reacted neutral triethanolamine resinate in proportion falling within the range of 4 per cent to 33 per cent of said ink.

RICHARD A. DENTON.

UNITED STATES PATENTS The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,335,882 Pingarron Dec. 7, 1943 FOREIGN PATENTS Number Country Date 468,384 Great Britain July 2, 1937 

